Mechanism for reciprocating brush carriages of selector switches or the like



Dec. 6, 1949 G. DEAKIN 2,490,035

MECHANISM FOR RECIPROCATING BRUSH CARRIAGES 0F SELECTOR SWITCHES OR THELIKE 2 Sheets-Sheet 1 Filed Feb. 23, 1945 INVENTOR. GERALD DEAKKN AGENTDec. 6, 1949 G DEAKIN 2,490,035

MECHANISM FOR RECI PROCATING BRUSH CARRIAGES OF SELECTOR SWITCHES OR THELIKE 2 Sheets-Sheet 2 Filed Feb. 25, 1945 I FIG. 4. 52 59 55 .56

INVENTOR. GERALD DEAKIN AGENT Patented Dec. 6, 1949 MECHANISM FORCARRIAGES OF THE LIKE Gerald Deakin, New

RECIPROCATING BRUSH SELECTOR SWITCHES OB York, N. Y., assignor toInternational Standard Electric Corporation, New York, N. Y., acorporation of Delaware Application February 23, 1945, Serial No.579,367

13 Claims. 1

This invention relates to means for drivin reciprocatory carriages suchas brush carriages of selector switches, for example switches of thischaracter used in automatic telephone systems as finder switches, groupselectors, final connectors, marking switches or the like.

An object of the invention is to provide an endless or continuous beltdrive for a reciprocatory brush carriage or the like which is novel andadvantageous in construction and operation, which is easy to assembleand economical to manufacture, and which will operate satisfactorilyover long periods of service with a minimum of attention.

Another object of the invention is to provide for a reciprocatorycarriage a drive which will operate with a minimum of noise.

Still another object of the invention is to provide a carriage drive inwhich a reciprocatory brush carriage is reoiprocated across a flatterminal bank by a flexible band which is driven in one direction only.

A further object of the invention is to provide means for gripping thereciprocatory carriage to either run of an endless belt in accordancewith the desired direction of carriage movement.

A still further object of the invention is to provide means whereby abrush carriage or the like is reciprocated by means in which acontinuous belt is driven in one direction only and a belt gripping orclutching device is sprung for operation in the opposite direction, ateach end of a carriage stroke.

Another object of the invention is to provide a reciprocating-carriagedrive whereby two reciprocatory brush carriages may be reciprocated onopposite sides of the same bay from a centrally located vertical shaft,thus reducing the vertical shaft equipment by one-half.

Other objects features and advantages will appear upon consideration ofthe following detailed description and of the drawings in which Fig. 1is a fragmentary section as seen from above, illustrating one embodimentof the invent-ion;

Fig. 2 is a sectional view taken along the line 2-2 of Fig. 1;

Fig. 3 is a sectional view taken along the line 3-3 of Fig. 1;

Fig. 4 is a view of the belt gripping means on the brush carriageshowing it as gripping one run of the belt.

Fig. 5 is a view similar to Fig. 4 but showing the belt gripping meansjust after release of one run of the belt and the gripping of the otherrun of the belt for movement of the brush carriage in the oppositedirection;

Fig. 6 is a section taken along the line 6-5 of Fig. 4; and.

Fig. 7 is a section taken along the line 'l-'I of Fig. 5.

Referring more particularly to Figs. 1 and 6, a supporting frame I of abrush carriage 2 is mounted to slide along a horizontal guide or rod 3and is held against swinging about said rod 3 by a guide or rod 4 (Fig.6) which extends slidably through a slot or groove 5 in a depending partof the brush-carriage frame. Such guides or guide rods 3 and 4 aresecured at their ends to frame members 6 and I which may form part of acasing 8 in which the brush carriage is reciprocated.

The brush carriage frame I may be considered as made up of two parts, aninner part and an outer part. Said inner part (Fig. 1) carries brushmeans to cooperate with terminals 9 of a flat terminal bank !0 and thebrush carriage proper will not be described further inasmuch as it isdescribed and claimed in my copending patent application Ser. No.576,797, filed Feb. 8, 1945, and is no part of the present invention.Said outer part of the brush carriage frame carries the belt-grippingmeans. These two parts of the carriage frame may be permanentlyconnected together or may be detachably connected which would enableeither part to be reversed with respect to the other.

Said outer part of the supporting frame of the brush carriage 2 carriesgripping means to cooperate alternately with parallel runs of acontinuous or endless belt [2 which is driven in one direction only.Preferably said belt I2 is made of suitable textile or plastic material.The endless belt drive and the gripping means on the brush carriageconstitutes important parts of the present invention. As illustrated inFig. l, the endless belt l2 passes around a pulley 13 at one end of thecasing 8 and from this pulley l3 extend parallel runs which at theopposite end of the casing 8 pass between two guide rollers H and thendiverge through openings l5 in frame or casing member 6 to the outsideof the casing where the belt l2 passes around a large driving pulley orwheel l6 fixed on a short or stu'b shaft 11 journaled in a bracket I8constituting part of the frame of the assembled machine. The belt may bekept taut and shock it may be mounted between stiffener beneath 7 otherend of the of gear upwardly Obviously energization of the magnet 29 willswing arm 3| downwardly against the action of absorbed to some extent bypivotally mounting the pulley [3 on a frame l9 pivoted at 2d and urgedin the proper direction by means of a compression spring 25 and anadjusting screw 22 held in adjustment by a lock nut 23.

The driving pulley It for the belt I2 is driven by suitable clutchmechanism from a vertical shaft 24 which is motor driven in a mannerthat is well known in so-ca11ed rotary telephone exchange systems.Preferablythe clutching mechanism is similar to clutching mechanismalready in use and comprises a thin flexible gear 25 secured to thelower end of stub shaft ii. A gear 26 is secured on shaft 24 to'rotatetherewith and to mesh with gear 25, but gear 25 may be flexed so as todisconnect it from said gear 28. In order to provide teeth of suitablethinness for gear '26, this gear may be in the form of a thin disc anddiscs 2? and 28 of which the larger disc 21 may assist in maintainingthe gears 25 and 26 in proper alignment while in mesh with each other.

The clutch is controlled by a clutch magnet 29 mounted on a fiange ofbracket IS with its pivoted armature 30 at the bottom thereof. An

extends from the armature to a point the flexible gear 25 near the pointof engagement between the gears 25 and 26 so that When the armature arm3| is lifted it will flex gear 25 out of engagement with gear 2%. Themovement of arm 3! and flexing ofthe gear 25 may be regulated as bymeans of a set screw 32 in the arm 3! and a set screw 33 in the bracketis to limit the upward tion of the flexible gear 25.

Upward movement of the arm 3! may be effected by means such as a leafspring 34, fulcrumed on a bracket 35. A set screw 36 threaded in bracketis acts on one end of the spring and may be adjusted to produce at thespring the desired upward presto deflect the adjacent part to disengageit from gear 25.

sure against arm 3| spring 34 and permit gear 25 to mesh with gear 23and be driven thereby. Subsequent deenergization of the magnet willresult in disengagement of flexible gear 25 from driving gear 26.

The clutch magnet 29 to be energized may be determined by dialing andmay be de-energized by finding a proper terminal. Such clutch magnetoperation is well known as evidenced by my prior Patent No. 2,336,471,December 14, 1943.

Referring to Figs. 4, 5 and v6 the belt-gripping device is shown asmounted on a sub-frame 38 constituting the outer part of the brushcarriage frame 1 and to which the inner part carrying the brushes isattached for support thereby. The parallel runs of the belt [2 passimmediately above the flat body of the frame portion 3a which isslidably supported at its front or side toward per jaw 43, preferablytoothed, on a pivot 44 at the upper other run abutment face of the frameportion 38. of belt [2 passes just to the rear of an 42a at the left andfront of frame pore movement of the displaced porin position by saidnuts. spring are detents such as ball detents comprisand hold the jaw ineither gripping 7 intermediate point a This movement of the right handverse change in the bers may be made of any suitable material such asmetal or plastic material.

Above the jaws the shanks of said bolts pass through correspondingperforations in the central portion of a leaf spring 58 which is securedAt the ends of said leaf ing in each case a ball 49 (Fig. 6) held in asocket formed in the spring and adapted to snap into either one of tworecesses 50 in the adjacent jaw or idle position. To throw one jaw 43into gripping position as the otherv is moved out of position the jawsA3 are provided with overlapping lugs or tails 5! so that when one jaw4-3, for example the right on Figs. 4 and 5, is thrown from itseffective position (Fig. 4) to its ineffective position (Fig. 5) thetail 5! thereon will act on tail 5| of the left hand jaw and swing it toeffective position with reference to the other run of the belt, thecorresponding detents acting together to assist in completing suchmovements. 7

To shift either jaw 43 from its effective position at the end of acarriage stroke, there may be provided at the opposite face of framemember 33 from the jaw, slides 52 each having at an longitudinal slot 53throughwhich passes a pivot or pin 54 fixed with reference to part 38,and at its inner end a pivot or pin 55 which is fixed with reference toslide 52 and passes through an inwardly inclined slot 56 in member 38and over the adjacent run of the belt. Thus when the carriage with theparts positioned as indicated in Fig. 4 moves to the left until roller51 pivoted on the upper or outer slide 52 strikes an abutment or buffer58, the slide is held against further movement in that direction.However, the carriage continues its movement to the left and the righthand end of the slide due to inclined slot 53 is moVed inwardly and thepin 55 acts through the belt l2 to swin the corresponding dog or jaw 43in a clockwise direction to release the corresponding run of the beltIE. or outer jaw 4.3 is transmitted through tails 5! to turn the lefthand jaw in a counter-clockwise direction for movement to effectivegripping position. A regripping devices will occur when the carriagereaches the other end of its path and the corresponding roller 5?strikes an abutment 58.

After a slide 52 has acted to cause movement of one jaw 43 from aneffective position to an ineffective position and vice versa for theother jaw, the slide must be returned to its outermost or normalposition. Preferably such return may be effected by a helicalcompression spring 59 interposed between said slides and at such aninclination that the spring will urge the slides 52 away from each otherboth longitudinally and transversely. As indicated in Fig. 4, the spring59 is interposed between abutments 68 on said slides and is retained inengagement therewith by pins 51 projecting from said abutments into theends of said spring. Obviously the spring 59 will tend to absorb theshock of stopping the carriage and to assist in reversing the movementthereof.

Certain details of the operating and guiding means for a slide 52 areillustrated in Fig. 7. Preferably the pin 54 has a shank passing throughthe slot 53 of the slide and a round opening in the flat body 38, and isheld against substantial longitudinal movement by a head 62 in a recesscountersunk in the face of member 38 at the opposite side from slide 52and by a nut 63 on a reduced threaded end of pin 54. The nut 63 islimited in its tightening movement by the shoulder at the end of thethreaded reduced portion of the shank and acts to hold the slide on thepin without interference with the sliding and swinging movement of theslide.

The pivot 55 has a. shank extending through the slot 56 in part 38 andjust beyond the far edge of the adjacent run of belt I 2, where it isprovided with a head 65. At its opposite end, the shank has a, reducedportion passing through a hole in the slide 52 and threaded at its outerend to receive a nut 66 by which the slide may be clamped firmly againstthe shoulder at the adjacent end of the shank proper. Mounted on saidshank are a roller 64 of suitable material such as red fibre, adjacentto said head 65 for engagement with the belt, a washer or spacer 68 in acountersunk opening in frame portion 38 and forming a marginaldepress1on around the inclined slot at the face of part 38 adjacent thejaws 43, and a second roller 69 to fit in said inclined slot 56. Rollers57 and 69 obviously tend to reduce friction and vibration.

The roller 51 at the outer end of each slide 52 of suitable material tominimize noise and vibration, such as neoprene, and may be mounted ahead H and a reduced end 72 extending through a suitable opening inslide 52 and secured to the slide as by riveting.

It should be noted that the toothed gripping faces of the jaws 43 wheneffective for gripping corresponding pivot 44 is to the front thereof.As a result of this arrangement, downward pressure on the upper reach ofthe belt [2 will throw the upper jaw member 43 downward and withdraw theright hand end of the toothed face of this jaw downwardly more rapidlythan the left hand end. The belt will then be separated from the fixedabutment 42 and will engage only the other end of said toothed face.Also the adjacent portion of the belt will be inclined downwardly and tothe left and beneath revolving roller 69. For the lower reach of thebelt, the belt will be deflected upwardly and the corresponding jaw 43in the same direction.

As illustrated in Figs. 1 and 2,

respect to two clutches of the flexible gear type on both sides of thesame bay,-both clutches being used to drive brush carriages. In the formshown, the bracket 18 carrying the second clutching device is invertedwith the belt pulley I6 below both the bracket l8 and the flexible gear25. Also the second flexible gear 25 is above the first mentioneddriving gear 25 and therefore a second gear 26 is provided at a higherlevel. For convenience the two gears 26 may be combined together, as bymounting them on a single sleeve,

24 may be increased as desired by superimposing such units.

The operation of the drive for the brush carriage '2 will now bedescribed briefly. The vertical shaft 24 revolves in a clockwisedirection and unless the clutch magnet 29 is energized, the flexiblegear 25 is held flexed out of connection or mesh with gear 25, the lowerone in Fig. 2, and the belt-drivin pulley l6 at the upper left of Fig. 1will remain at rest. Such flexing is effected by pressure of set screw32 on armature arm 3| under the influence of the adjustable leaf spring34. However, energization of the clutch magnet 29, due to selectivedialing will act to swing the armature arm 3! downwardly against theaction of spring 34 to permit flexible gear 25 to come into gear or meshwith the lower driving gear 26. The flexible gear 25 will then turn in acounterclockwise direction and cause the outer run or reach of endlessbelt I 2 to move to the left and the inner run to move to the right. Thebrush carriage, when gripped to the outer reach or run, will travel tothe left until the end of its path is reached. At this time the brushcarriage is reconnection will again be reversed. Deenergization of theclutch magnet will disconnect the clutch and the belt I 2 will come torest.

The belt gripping device is always effective to grip one of said tworuns of the driving belt. As the brush carriage approaches the left endof its path, the roller 51 on the leading slide 52 engages the buffer 58and this slide is stopped while the carriage continues to advanceagainst the action of spring 59. The pin 54 then moves to the left inthe slot 53 and the inclined slot 56 forces the pin 55 downwardly andconsequently swings the right end of the slide 52 downwardly about pingages the outer run of the belt in advance of the gripped portion, andexerts pressure therethrough to throw the adjacent dog or jaw 43 awayfrom the abutment 42. This causes the corresponding ball detent on theflat spring 48 to snap from the gripping recess 55 to the idle recess59. This movement of the adjacent jaw 43 is transmitted through the lugsor tails 5| of said gripping memhere to the inner or lower gripping jaw43 which is snapped to effective position to grip the inner run of thebelt, the snapping action being effected by the ball detent associatedwith the last-mentioned jaw 43.

Upon reversal of movement of the brush carriage, the roller 5'5 whichengages the buffer 58 remains in engagement therewith until the spring59 has expanded sufficiently for the right end of slot 53 to engage pin54 and the pin 55 to reach its normal position at the high end ofinclined slot 56. This shifting of the gripping action from one run tothe other will continue as long as the belt [2 continues to travel.

It will be seen that a very small movement of the gripped run of thebelt by the roller on the adjacent pin 55 will be sufficient to causethe corresponding jaw 43 to snap to ineffective position, due to theapplication of the jaw-shifting action of the belt at a point muchcloser to the axis than the detent device. This enables the gripping ofthe outer run of the belt to be released before contact if any betweenthe roller on pin 55 and the end of the slot 56. Furthermore, there issufficient lag between the release ZAQQQSiS of; the upper r ppi deviceErie;- a d efieotive gripping of the lower run to avoid excessive shock,parti u ar y n V ew o t e ur in of the cal-Imagein reverse direction bythe compressed spr n 5 r- Although metal band-s and other metal beltscould be used for" the belt l2, they would have the disadvantageous;features of noise, the possibility of transmitting vibration and thepossibili-ty of corrosion. Preferably use should be made. of: atextileor; plastic belt i2. A belt of this character should be noiseless andpractically free from vibration because of, the slow speed and thedamping nature of the textiles and plastics. The proper belt should becapable of standing all climatic conditionsv and of holding the brushcarriagein position,

Although oneembodiment of the invention has been shown and described forthe purpose of illustration, modifications occurring to those skilled inthe art may be made without departing from scope of the invention asdefined in "re appended claims.

What is claimed is;

1. In a selector switch ofthe kind used in automatic telephonesystems orthe like, the combination, with a brush carriage mounted forreciprocation; along a flat terminal bank, ofmeans for reciprocatingsaid carriage including an endless driving belt having two parallel runsarranged to travel in opposite directions, gripping means on said arriae posi ioned adjacent o h Qt sa runs, and adapted to engage either ofsaid runs for movement ofthe carriage inone direction with one and in;the opposite; direction with the other of said runs, respectively, andbelt deflecting means operative upon arrival of said carriage ineitherof twoextreme positions to deflect a respective run so asto disengagesaid gripping means. from; the deflected run and engage said grippingmeans with the undefiected run, whereby the direction of travel of saidcarriage will be reversed.

2. The combination according to claim 1 wherein said gripping meanscomprises a pair or pivoted members each having an effective and an.inefiective position, said members being provided with means operativelylinking them togather so that each member will assume its efiectiveposition when the other member is forced into its ineffective position.

3. The combination according to claim 2, further comprising resilientdetent means arranged to, locate, each of said members alternatively inthe said effective or ineffective position thereof.

4, The combination according to claim 1 wherein said gripping meanscomprise a pair of members each having a belt-engaging surface and pivotmeans rotatably securing said members to, said carriage, sa d pivotmeans being displaced with respect to the, belt-engaging surface of arespective member in the general direction of travel of the respectivebelt run engageable by said member, said deflecting means comprising apair of projections each associated with a respective member andarranged to bear upon the respective run engageable by the associatedmember at a point which is displaced with respect to the belt-engagingsurface of said associated member in the general direction of travel ofsaid respective run by a lesser distance than the said pivot meanssecuring said associated member to said carriage.

5. In an apparatus. of the general character described, a carriagereciprocable along a linear a s tionarrbufier at ech en p air aths anendless driving belt having two runs extend ins on p ite id s said caria e pa l e to said path, said runs being arranged to travel in oppositedirections;- gripping means on said carriage alternatively engageablewith either of said runs for displacing said carriage in a respeetivedirection along said path; and mechanism for reversing the direction oftravel of said carriage upon approach of either of said bumpers,saidmechanism comprising a pair of members displaceablerelative to saidgripping means, each of said members having a normal position and beingengageable by a respective bumper for dis,- placement into. anofi-normal position in which said member operativel-y bears upon saidgripping means to move the latter out of contact with one and intocontact with the other of said belt runs, and springmeans for restoringeach of said members to its normal position upon disengagement from arespective bumper.

6. Thecombination according to claim 5 where in each, of said members isarranged to bear upon said gripping means through the intermediary oi, arespective belt run.

7. The combination according to claim 5 wherein said carriage isprovided with a pair of elongatedslots inclined toward said path, saidmechanism further comprising guide means allowing iior longitudinal andpivotal movement of said members, each of; said members being providedwith a projection slidably held in a respective one; of said slots. andarranged to operatively bear upon said gripping means upon longitudinaldisplacement of; the member through engagement witha respective bumper.

8. The combination according to claim 7 wherein each oi said.projections is arranged to bear upon said gripping means through theintermediary of a respective belt run.

9.. A mechanism for reciprocating contact brushes or the like along alinear path, a carriage displaceable along said path, a stationarybuffer at each end of said path, an endless driving belt having two runsextending on opposite sides of, said carriage parallel to said ath, saidruns being arranged to travel in opposite directions, a pair of jawseach associated with a respective belt run, each of said jaws beingprovided with a belt-gripping surface facing the associatedrun, pivotmeans swingably securing said jaws to said carriage, said jaws beingthus swin able from an ineiiective position into an effective positionin which the said belt-gripping surface of the jaw engages theassociated belt run whereby the carriage will be entrained in thedirection of travel of the run thus engaged, said members being furtherprovided with lug means operatively linking them together so that eachmember will assume its efiective position when the other member is swunginto its ineffective position, a pair of slides, guide means securingsaid slides to said carriage while permitting longitudinal and pivotalmovement of said slides, said carriage being provided with a pair ofelongated slots inclined toward said path, each of said slides have inan extremity carrying a projection slidable in one of said slots havinganother extremity engageable by a respective bumper to displace theslide from a normal position whereby said projection-carrying extremitythereof will operatively bear upon a respective jaw to disengage thesame. from its associated belt run and swing said jaw into itsineffective position, and spring means for restoring each of said slidesto its normal position upon disengagement from a respective bumper.

10. A mechanism according to claim 9 wherein each of said jaws is formedwith a pair of holes, further comprising a flexible member secured tosaid carriage and carrying a pair of ball detents each arranged tocooperate with a respective pair of holes so as to locate each jawalternatively in the said efiective or ineffective position thereof.

11. A mechanism according to claim 9 wherein each of saidprojection-carrying extremities is arranged to bear upon a respectivejaw through the intermediary of the associated belt run.

12. A mechanism according to claim 11 wherein said pivot means comprisea pair of studs each displaced relative to the belt-engaging surface ofthe respective jaw secured thereto in the general direction of travel ofthe associated belt run, the said projection-carrying extremity of arespective slide being arranged to bear upon said associated belt run ata point which is displaced relative to said belt-engaging surface in thesame 10 general direction but by a lesser distance than the respectivestud.

13. A mechanism according to claim 12 wherein of saidprojection-carrying extremities n s a roller engageable with arespective belt GERALD DEAKIN.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,472,818 Waller Nov. 6, 19231,611,854 Darmow 1- Dec. 21, 1926 1,774,356 Cloud Aug. 26, 19302,073,087 Wirth Mar. 9, 1937 2,123,228 Carpenter July 12, 1938 2,197,501Holden Apr. 16, 1940 2,240,039 Hickman Apr. 29, 1941 2,330,812 DeakinOct. 5, 19 :3

